About the Authors

Esther G. Gerrits

esther.gerrits@mumc.nl

Affiliations Department of Internal Medicine, Maastricht University Medical Center, Maastricht, The Netherlands, Diabetes Centre, Isala Clinics, Zwolle, The Netherlands

Alaa Alkhalaf

Affiliations Diabetes Centre, Isala Clinics, Zwolle, The Netherlands, Department of Gastroenterology, Isala Clinics, Zwolle, The Netherlands

Gijs W. D. Landman

Affiliation Diabetes Centre, Isala Clinics, Zwolle, The Netherlands

Kornelis J. J. van Hateren

Affiliations Diabetes Centre, Isala Clinics, Zwolle, The Netherlands, Langerhans Medical Research Group, Zwolle, The Netherlands

Klaas H. Groenier

Affiliations Diabetes Centre, Isala Clinics, Zwolle, The Netherlands, Department of General Practice, University Medical Center Groningen, Groningen, The Netherlands

Joachim Struck

Affiliation Thermo Fisher Scientific, BRAHMS Biomarkers, Research Department, Hennigsdorf, Germany

Janin Schulte

Affiliation Thermo Fisher Scientific, BRAHMS Biomarkers, Research Department, Hennigsdorf, Germany

Reinold O. B. Gans

Affiliation Department of Internal Medicine, University Medical Center Groningen, Groningen, The Netherlands

Stephan J. L. Bakker

Affiliation Department of Internal Medicine, University Medical Center Groningen, Groningen, The Netherlands

Nanne Kleefstra

Affiliations Diabetes Centre, Isala Clinics, Zwolle, The Netherlands, Langerhans Medical Research Group, Zwolle, The Netherlands, Department of Internal Medicine, University Medical Center Groningen, Groningen, The Netherlands

Henk J. G. Bilo

Affiliations Diabetes Centre, Isala Clinics, Zwolle, The Netherlands, Department of Internal Medicine, University Medical Center Groningen, Groningen, The Netherlands, Department of Internal Medicine, Isala Clinics, Zwolle, The Netherlands

Competing Interests

Coauthor J. Struck was formerly employed by the commercial company Thermo Fisher Scientific and is currently employed by Sphingotec GmbH and coauthor J. Schulte is employed by the commercial company Thermo Fisher Scientific. This does not alter our adherence to PLOS ONE policies on sharing data and materials and there are no restrictions on sharing of data and/or materials.

Author Contributions

Performed the experiments: KHG NK. Analyzed the data: EGG. Contributed reagents/materials/analysis tools: J. Schulte J. Struck. Wrote the paper: EGG AA GWDL KJJH ROBG SJLB HJGB.